Filament-supports for incandescent lamps.



G. P. STEINMETZ.

FILAMENT SUPPORTS FOR INUANDESGENT LAMPS.

' APPLICATION FILED JULY 28, 1905.

1,013,965 Patented Jan. 9, 1912.

run s'rnrns Parana ensues.

CHARLES P. STEIN'METZ, OF SCHEINECTADY, NEW YORK, ASSIGNOR TO GENERAL FILAMENT-SUPPORTS FOR .INOANDESOENT LAMPS.

Specification of Letters Patent.

Patented c n. a, rate.

Application filed July 28, 1905. Serial No. 271,605. I

To all cvhom it may concern:

Be it known that I, CHARLES P. STEIN,

METZ, a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Filament- Sup orts for Incandescent Lamps, of which the allowing is a specification.

In tantalum and other incandescent lamp utilizing a filament which is not rigid enoug at incandescent temperature to be self-supporting, it has been found convenient to mount the filament from a plurality of supports and thus prevent contact between adjacent convolutions of the filaments at all times. Tantalum filaments have been found to undergo certain progressive changes afiecting the mechanical structure of the filament and apparently producing globules or other enlargements along the filament separated by parts of smaller cross-section. This action materially contracts the filament so thatit becomes tightly stretched between the r1gid supports and frequently breaks when the lamp is extinguished and the filament cools down. I

It is the object of this "invention to provide a resilient supporting means for tentalum and similar filaments whereby a considerable range of expansion and contraction is permissible -without subjecting the filament to severe strains.

My invention will be better understood by reference to the drawing forming a part of this specification in which,

Figure 1 1s a perspectwe view of one ,modification of my improved supporting means; and Fig. 2 is a second modification.

A lamp socket 1 of ordinary form is provided with an exhausted globe 2, which if perspective view of a desired may be frosted- The usual hollow glass stem extends inward from the socket,

and a glass part 3 projects from this stem.

The supporting member thus formed, some times termed a pedestal, carries near the baseof the globe 2 a ring 4 around which a plurality of coiled springs 5 are arranged at regular. intervals, and at its upper. end a second ring 6 provided with hooks 7 adapted to sup ort the incandescent filament.

The lead w1res 8 and 9 aresealed in the glass.

stem at the base of the pedestal in the usual manner, andare connected to the terminals IOand ll of the filament. The latter is supported in a plurality of loops from the hooks 7 and at the bend at the lower end of each loop is connected one of the hooked ends of the coiled springs 5. The coiled springs are adapted to prevent displacement of the loops and at the same time to permit a very considerable expansion and contraction of the filament without producing any strain sufficient to break the filament.

The modification shown in Fig. 2 embodies a somewhat difi'erent means for supportingthe filament. The central pedestal 12 is provided at its top with a slightly enlarged hub 13 carrying radial arms 14 provided at their ends with hooks which support successive loopsof the filament. The pedestal is also provided at its base with a second hub 15 from which radiate a plurality of coiled springs 16 provided. at their outer ends with hooks to engage the lower ends of the loops of the filament. It will be readily understood that by arranging the coiled springs so that the fiexure is transverse to the axis of the springs the adjustment may be made very delicate and the ends of the springs will pass through a considerable distance without materially increasing the pull on the filament loops.

Both of the modifications above described have the further advantage of protecting the filament from shocks or jars during handling as the coiled springs tend to deaden theforce of such shocks and thus prevent their transmission to the filament.

What I claim as new and desire to secure by Letters Patent of the United States, is,:-

1. In an incandescent lamp, the combination with a fragile metal filament of a plurality of coiled springs supporting said filament at a plurality of oints in its length so as to permit contraction thereof.

2. In an incandescent lamp, the combination with a filament supported in a pluports forsaid filament, 'anda plurality of tension regulating devices engagmg the filament between adjacent filament supports, each of said devices acting upon the portion of the filament engaged by it independently I points intermediate said supports.

7. In an incandescent lamp, the combination with a metal filament comprising a plurality of 100 s of resilient supporting means exertin a irect pull upon each loop for protecting said filament from strains due to contraction.

8. In an incandescent lamp, the combination of a central pedestal, a plurality of supports arranged aboutsaid pedestal, a metal filament carried by said supports, and

.a plurality of coil springs attached to said filament to maintain it in proper position on said supports.

9. In an incandescent lamp, the combination with a metal filament loop ofa su porting spring engaging the bend of said loop and subject to transverse fiexure from the contraction of said filament loop.

10. In an incandescent lamp, the combination with a metal filament of a coiled spring engaging the filament between its ends and disposed at an angle'thereto.

11. In an incandescent lamp, the combina tion with a metal filament of a coiled spring therefor subject to transverse fiexure on contraction of said filament.

12. The combination with a metal filament loop, of a coiled spring engaging therewith and subject to transverse fiexure on contraction of said locp.

13.. The combination with a metal filament arranged in a loop of a coiled spring engaging said loop and disposed at substantially a right angle to said loop.

14. In an incandescent lamp, the combination. with a fragile metal filament loop of a relatively ri id supporting member outside the plane 0 said loop and a resilient element projecting from said member and engaging the bend of said loop.

15. The combination of a fragile filament disposed in a loop adjacent a central pedestal and a spring projecting radially from said pedestal and engaging with said loop to prevent displacement thereof.

16. The combination with a supporting member of a fragile metal filament loop hav-. ing its ends carried from said member, and

a resilient element secured to said supporting member and engaging the bend of said loo 1%. The combination with a fragile filament loop of a coiled spring engaging w th one end thereof and subject to compression when said filament is subjected to transverse shock. I

18'. In an incandescent lamp, the combination of a pedestal support suitably mounted therein, a filament loop having its ends carried from said pedestal, and a resilient element extraneous to. the 'circuit through said loop engaging the same and secured to said pedestal support, said resili: ent element yieldingly resisting movement of the loop ina transverse direction.

19. The combination of a supporting member, a filament arranged about said member in a plurality of loops, and a plurality of springs projecting radially from said member and engaging the bends of said loops.

20. The combination of a suitable supporting member, supporting devices projecting from said member which comprise springs and suitable filament-engaging portions, and a filament arranged about said member in a plurality of loops having their bends engaged by the filament-engaging portions of said supporting devices, said springs serving to maintain the filament in position and protect it from shock, and said supporting devices responding independently to variations in the length of the loops.

21. The combination with a plurality of adjacent filament loops of suitable supportmg meansengaging the bends of said filamentloops and affording them yieldingsupport, said sup orting means comprising springs which yieldingly resist movement of said loops toward one another.

22. The combination with a plurality of filament loops grouped about a supporting member of suitable supporting means for the bends of said loops comprising supporting elements that extend transversely with reference to the filament loops and are carried from said supporting member and engage with the filament, said supporting means acting upon the bends of the filament to urge them in the longitudinal direction of the loops while resiliently yielding to allow variations in the length of the loops.

23. The combination with a filament loop of a supporting device for the bend of the loop comprising a spring subject to transverse flexure upon contraction'of the-filament and a relatively rigid supporting minnber lying outside the plane of the loop, the part of said device'engaging with the loop extending transversely with reference there to and being carried from said'supporting of a supporting element engaging said loop and extending transversely with reference thereto, said element afi'ording the filament resiliently yielding support and acting to keep it taut, and the part of said element engaging with the filament being free .to move in the longitudinal direction of the loop with every variation in its length.

In witness whereof, I have hereunto set my handthis 27th day of July, 1905.

CHARLES P. STEINMETZ.

Witnesses: I I

BENJAMIN B. H LL, HELENA Smnms. 

